JPS6257514B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to typewriter keyboards and, more particularly, to returning components in a typewriter to a rest position.
Prior art typewriter keyboards, such as those included in the IBM Model 72 typewriter, utilize a keylever with a keylever pawl or bar mounted on the keylever that is itself rotatably mounted. The key lever pawl is held in its rest position by a comb or a leaf or coil spring connected between the pawl and the key lever. When a character is selected by pressing the key lever, the key lever engages with the shaft of the interposer below the selected key lever.
Once the pawl has pushed the interposer down to its selected operating position and the keyboard has cycled to effectuate the interposer selection, the interposer returns to engage the key lever pawl and exert a force on it, forcing it onto the interposer shaft. It is removed from the path and biases the spring acting on the claw. When the key lever is returned, a pawl return spring returns the pawl to its normal active position above the interposer shaft. When the key lever pawl is removed from its normal position, the interposer can recover and holding the key lever down during a keyboard cycle will not affect the time required for the next selection. .

When attaching each spring to the key lever pawl, an assembly problem arises in which the springs must be connected in a tight fit between the key lever pawl and the key shaft, which requires troublesome and time-consuming work to handle a large number of springs. Become.
Comb-shaped springs require expensive tooling and very careful handling and assembly.

It is an object of the present invention to eliminate the large number of springs required to return a key lever pawl to a key lever in a typewriter keyboard.

A second object of the invention is to simplify the assembly of typewriter keyboards by incorporating a single elastic tubular spring for returning the keyboard pawl.

A hollow rubber tubular member that can be deformed under a relatively small force and collide locally with the tube and has sufficient elasticity to provide a return force to the key lever pawl when released is placed under the key lever. By inserting it laterally and holding it in effective spatial relationship with the key lever pawl, the disadvantages of the prior art are overcome and the objects of the present invention are achieved.

The hollow tube has an open end hole such that the key lever pawl receives only the local deformation forces of the tube as it attempts to return to its original undeformed position.
The resulting force is transmitted to the key lever pawl, causing it to return to its normal rest position. A tubular spring is inserted across the entire keyboard, so that one tubular member can be used to apply force to all key lever pawls, regardless of their relative lateral positions on the keyboard.

In order to provide a more complete and detailed understanding of the structure and operation of the present invention, reference will now be made to the drawings.

The keyboard of an office appliance, such as a typewriter, has key buttons 10 and a key lever 12 for inputting desired information into the typewriter or appliance. key lever 12
is typically rotatably mounted on pivot 14. The pivot 14 extends across the entire keyboard and all key levers 1
It is a common pivot for 2. A key lever pawl 16 is loaded on the key lever 12.
The keyboard pawl 16 is also provided with a stop lug 20 for preventing the key lever pawl 16 from passing a predetermined desired position with respect to the key lever 12. Stop lug 20 is
This is effective in stopping the movement of the key lever pawl 16 in the clockwise direction as shown in the drawings in order to align the key lever pawl 16 with the interposer shaft portion 36.

Extending from the lower side of the key lever 12 is a supporting attachment 22 generally configured with a hook. This supporting attachment 22, together with similar supporting attachments 22 of other key levers, restrains the movement of the tubular spring 24. Tubular spring 2
4 rests on the upper surface of the supporting attachment 22 and is effectively captured between the key lever pawl 16 and the attachment 22. The attached part 22 has a structure that allows the key lever 12 to be attached to the pivot 1 above the tubular spring 24 and on the underside of the lower side of the key lever without being caught on the top of the tubular spring 24.
Sufficient clearance is provided to allow rotation around 4 to its active position. The upper position of the key lever 12, ie the normally returned position, is defined by the key lever upstop 26.
The lateral stability of the key lever 12 is determined by the key lever 1
2 is provided by a front comb-shaped guide member 28 which limits the range of lateral and downward movement of 2. The return of the key lever 12 when released is such that the other end is fixed to a portion of the frame of the typewriter keyboard by a return spring bracket 32.
This is achieved by a key lever return spring 30, which is a leaf spring that engages the lower side surface of the key lever 12.

Below each key lever 12 on the keyboard,
An interposer 34 is arranged. Interposer 34 includes multiple codes that can be removed or left in place depending on the type of character encoding desired from each particular key lever.
A lug 33 is provided. interposer 34
A shaft portion 36 extends upwardly from the top. Shaft portion 36
has a flat area at one end for engaging the lower side of the key lever pawl 16. Furthermore, the shaft portion 36 has a back surface 38 that can engage with the front surface of the key lever pawl 16 .

The interposer 34 can be moved in the vertical direction by the comb-shaped guide member 42, but its movement in the lateral direction is restricted. The comb guide member 42 and the bracket 44 together form a race, with the comb guide member 42, the bracket 44 and the ball 46
A plurality of interposers 34 may be arranged to interlock movement into a ball coupling device formed from a plurality of interposers 34.

The filter shaft 50 can be driven periodically by a conventional single cycle clutch 52 or can be oscillated as a bail by a suitable linkage. The ribs 54 or longitudinal shafts 54 of the filter shaft 50 impact the depressed interposer 34 to provide the driving force necessary to vertically move the interposer 34 for character selection encoding. interposer 34
is provided with a hole 56 through which the fulcrum shaft 58 of the interposer passes.

Interposer fulcrum shaft 58 provides a sliding and rotating fulcrum for interposer 34 . Front interposer comb guide member 60 provides a lateral rotational fulcrum for keeping character interposer 34 in proper relationship with other interposers on the keyboard.

Return spring 48 acts to pull interposer 34 to its return position when released from external forces from filter shaft 50 and key lever pawl 16.

The general operation of a keyboard incorporating tubular springs 24 is quite similar to other keyboards previously commercially available. When the operator presses key button 10 and key lever 12, the key lever rotates about pivot 14, causing key lever pawl 16 to move downwardly. When the key lever pawl 16 moves downward, it engages with the top 37 of the interposer shaft 36. Thereby, the interposer 34 is rotated clockwise around the interposer fulcrum shaft 58, the rear end of the interposer is lowered, and the tip 61 of the interposer 62 is formed from the comb-shaped guide member 42 and the bracket 44. It is pressed between the balls 46 contained in the ball tube, thus interlocking the keyboard against subsequent pressing of the carrier interposer. When the interposer 34 is pushed, the rear end 35 of the interposer 34 will rotate into the longitudinal groove 54 of the filter shaft 50 in the next rotation.
Can be interlocked with. interposer 34
When engaged with flute 54, it moves vertically and generally to the left of the drawing to effectuate selective encoding of the selected character.

When flute 54 disengages distal end 35 of interposer 34, return spring 48 forces interposer 34 upwardly and to the right back to its rest position. When the interposer 34 returns to its rest position, the rear surface 38 of the shaft 36 engages the front surface of the key lever pawl 16 if the key lever 12 remains recessed due to the force of the operator's depression of the key button 10. Interposer 34 by return spring 48
When the key lever pawl 16 is fully pulled to its home or rest position, the force of the spring is transmitted through the shaft 36 to the key lever pawl 16, causing the key lever pawl 16 to move in a counterclockwise direction about the pivot bolt 18. .

At this time, the back of the key lever claw 16 is attached to the spring 24.
A tubular spring 24 made of elastic rubber or similar material collides with the force of the key lever pawl 16. The key lever pawl 16 continues to deform the tubular spring 24 until the operator removes the force exerted on the key button 10 and the key lever 12 rotates about its pivot 14 into engagement with the key lever upstop 26. When the key lever 12 is returned by the force of the key lever return spring 30 stored while the key lever 12 was pressed, the front end of the key lever pawl is disengaged from the back surface 38 of the interposer shaft portion 36. When this disengagement occurs, the resiliency of the tubular spring 24 and the force generated in the wall of the tubular spring 24 by the key lever pawl 16 act to force the resilient tubular spring 24 into its normal cross-sectional shape. , thus pushing the key lever pawl 16 in a clockwise direction to return it to its normal rest position defined by the engagement of the stop lug 20 and the lower side of the key lever.

A single tubular spring made of rubber or other easily deformable resilient material provides a restoring force to the key lever pawl 16 while also providing a restoring force to the key lever pawl 16 on other key levers 12 that have not returned to their normal rest position. Gives return force to other key lever pawls. This tubular spring is a simple and reliable improvement over the multiple key lever pawl springs commonly used heretofore in typewriter keyboards.

[Brief explanation of the drawing]

FIG. 1 is a partial perspective view of a keyboard incorporating a tubular spring for a key lever pawl. FIG. 2 is a partial end view of the keyboard showing the relationship of the key lever pawl tubular spring to the key lever and interposer when in the normal rest position. Third
The figure shows the position of each element on the keyboard when the key lever and interposer are pressed down to select the desired character. FIG. 4 shows an end view of the key lever with the interposer returning and applying force to the key lever pawl, causing the interposer to locally deform the tubular spring before the key lever is released. It is. 12...Key lever, 16...Key lever claw,
24...Tubular spring, 34...Interposer.

Claims (1)

[Claims] 1. A key lever; an interposer having at least one normal position; and a position transmitting the movement of the key lever to the interposer and transmitting the movement when acted upon by the interposer. a key lever pawl displaceably mounted on the key lever such that the interposer can be displaced from the relationship and thereby return the interposer to the normal position; A keyboard comprising an elastically deformable tubular member disposed intersecting the key lever so as to be deformed, thereby providing a restoring force to the pawl.